Attributable risk vs ARR

I was hoping someone could clarify something for me.

In terms of calculations, are attributable risk and absolute risk reductions the exact same thing? Is the only difference that we use AR for cohort studies (and therefore relative risk) and ARR for case-controls? Likewise, is the number needed to treat/harm the same thing as well (NNT for case-control and NNH for cohort studies)?

thanks!